Immunodeficiency-73A with defective neutrophil chemotaxis and leukocytosis (IMD73A) is an immunologic disorder characterized by onset of recurrent infections in early infancy. Affected infants have periumbilical erythema and later develop skin abscesses and invasive infections. Laboratory studies show leukocytosis, neutrophilia, decreased TRECs, and T-cell abnormalities. Neutrophils showed decreased chemotaxis associated with actin polymerization abnormalities, as well as variably impaired oxidative responses. Hematopoietic stem cell transplant may be curative (summary by Accetta et al., 2011; review by Lougaris et al., 2020). In a review of autosomal forms of chronic granulomatous disease (see 306400 for genetic heterogeneity of CGD), Roos et al. (2021) noted that patients with RAC2 mutations may manifest CGD-like symptoms due to defects in neutrophil NADPH oxidase activity. [from OMIM]